U.S. Patents covering technologies pertinent to the present invention include:
______________________________________ U.S. Pat. No. Inventor Date of Issue ______________________________________ 5333817 Kalisz 09/02/1994 5285986 Hagenlocher 02/15/1994 5115998 Olive 05/26/1992 5004633 Lovik 08/02/1991 4971269 Koda 11/20/1990 4966568 Nakamura 10/30/1990 4934631 Birbas 06/19/1990 4833837 Bonneau 05/30/1989 4766918 Odekirk 09/30/1988 4758199 Tillotson 07/19/1988 4711416 Regipa 12/08/1987 4434958 Rougeron 03/06/1984 4384435 Polise 05/24/1983 4113206 Wheeler 09/12/1978 4114325 Hochstein 09/19/1978 4024679 Rain 05/24/1977 4004380 Kwake 01/25/1977 3816885 Saether 06/18/1974 3744191 Bird 07/10/1973 3676276 Hirshen 07/11/1972 3620485 Gelhard 11/16/1971 3490184 Bird 01/20/1970 3456903 Papst 07/22/1969 3384328 McGee 05/21/1968 3369774 Struble 02/20/1968 3332176 Knetzer 07/25/1967 3247627 Bird 04/26/1966 3277724 Lundeberg 10/11/1966 2996212 O'Sullivan 09/15/1961 2986242 Clevett 05/30/1961 2463517 Chromak 03/08/1949 ______________________________________
The art of building composite structures of inflatable members spans many fields. Most common are structures built of latex balloons. These typically involve decorative bundles of balloons tied together and possibly tied to a supporting structure, such as an arch. These structures are time-consuming to construct due to difficulties in getting the balloons adjusted into desired geometries and it is impractical to deflate the balloons and leave the decorative arrangement intact. The balloons are typically used only once and then discarded. In addition, the balloons frequently fail during construction and strings become tangled causing frustration.
Another commonly seen method for building structures of multiple balloons is the art commonly seen in circuses of tying elastomeric balloons together to form animals and the like. This method requires considerable study, relies on latex balloons, does not form figures that are easily disassembled, and is not well suited to the construction of large structures.
U.S. Pat. No. 4,892,500 describes a network of elastomeric multi-spout balloons connected by plugs meant to remedy the difficulties in maintaining desired geometry. However, these structures rely on rigid devices for support and therefore compromise air-floatability. They are also quite complicated to interconnect, and rely on fragile latex balloons.
U.S. Pat. No. 4,944,709, describes three dimensional balloon sculptures and building blocks. These sculptures also seek to remedy the geometry problem by relying entirely on rod-like members keeping balloons in place. Air floatability is compromised, and the uses of the final structure are limited to static display.
A number of other means of connecting balloons have been presented, one example is U.S. Pat. No. 5,378,186. Here the connections are very complex and are designed to connect two non-elastomeric balloons together to form a single figure, as in a dog with a head. The method used by U.S. Pat. No. 5,378,186 involves two balloons joined by a tab on one balloon and a collar on another. It suffers from being time-consuming to use and the method can only be applied to a limited range of geometries.
U.S. Pat. No. 5,273,477 describes inflatable interlockable blocks with frictionally releasable interlocking tongues and grooves. These blocks are substantially two dimensional, since the faces of the blocks are connected together at a pattern of points other than the seams. These structures are not typically envisioned as being air-floatable and most require great size to achieve the required surface/volume ratio for lift with helium. In addition, they use frictional fastening systems and so cannot be used as a ball, require a very specialized shape for engagement, and have difficulty maintaining structural integrity in various states of inflation due to the reliance on a particular balloon shape for fasten ability.
U.S. Pat. No. 5,145,440 uses tube-like inflatable interlockable members with junctions stabilized by hook-and-loop fasteners to form life-size play structures shaped like log cabins. These structures are not typically envisioned as being air-floatable and require great size to achieve the required surface/volume ratio for lift with helium. In addition, they do not come apart readily since they are connected with both frictional and contact fasteners, with contact fasteners buried in the junction. They also are highly restrictive as to shape.
A water-puzzle currently being sold is composed of six inflatable rings connect able into a cube and other configurations by a total of seventy two grommets and thirty six split rings. This device with faces thirty inches across in the uninflated state weighs eighteen hundred grams and requires twenty minutes to assemble and disassemble. This device displays poor structural integrity when assembled.
Other inflatable toys commonly sold are of pre-connected inflatable members that are not typically re-configurable and have no special structural properties.
U.S. Pat. No. 4,836,787 describes a set of planar regular polygonal elements joined by hook-and-loop fasteners. These elements are not air-floatable, are rigidly restricted in geometry, and can be unsafe when thrown around the room by children.
U.S. Pat. No. 4,650,424 describes a toy for demonstrating characteristics of a latticework of space points based on gravity stacked ellipsoidal elements which may be optionally connected by hook-and-loop fasteners. The strong dependence on gravity in this patent precludes any designs for air-floatability. This patent is useful in locating where to place fasteners for spherical elements of a particular lattice, but does not describe the geometries of the contact fastening elements themselves.
Poole, in "Tensional Structures", demonstrates a half-dome constructed of inflatable hexagons and pentagons of plastic foil. This structure is not reconfigurable and as designed could not be assembled if the faces were individually inflated prior to connection into a structure, since the connections between balloons are too short to accommodate the three dimensional faces. This is not a problem for the housing-type applications this half-dome is designed for, and in fact is desirable since it increases the rigidity of the structure through pre-stressing as the dome is inflated.
Minke, in "Tensional Structures", demonstrates polyhedra built of flexibly connected inflatable polygons with internal frames. These structures cannot be made readily air-floatable, cannot act as one polygon on one side and another polygon on the other, and avoid challenges associated with three dimensional faces by using a frame so that faces can be treated as two dimensional objects.
The prior art for large inflatable balloons relies on large gores being sewn together to form a single large envelope. This technique is not suited to automated manufacture, and the resulting balloons are of a fixed shape.
U.S. Pat. No. 5,115,998 describes a double-walled annular balloon for satellite protection. This balloon requires 178 psi. to be inflated on earth and is designed to be permanently assembled into only one configuration.
Each instance of prior art suffers from a number of shortcomings this invention attempts to remedy.